Incidentally, here's an idea how the E-wing's canon could be compensated for, using a rough HUD mockup.
So certainly, in some cases an object might be lost in the cannon. The further away the object, the more it will be obscured. However...
All it takes is sensor data to extrapolate and superimpose the obscured object over the cannon on the HUD (in fact this could be applied to other visual blindspots, as well).
Frankly, it's unfair to single the E-wing out for obstructed views considering how horrible they are in virtually every fighter in the franchise. A TIE pilot wouldn't be able to see anywhere but straight ahead of him, and through four tiny slits overhead. The Y-wing may have the WORST visibility of any other ship in the franchise, with its heavily-framed canopy, and small forward viewport. The X-wing has almost no visibility aft at all, because of the tiny rear window obstructed by the astromech. The only starfighters in the Original Trilogy that have anything approaching a genuinely acceptable field of view are the A-wing and B-wing.

The closest we see to "shield splash" in the Trilogy are impact sparks, which are consistent throughout:
Note that the laser bolts themselves don't significantly illuminate anything, even though several are passing quite close to the X-wing. The shield "sparks" do, but that's something that could probably be filtered out, or at least mitigated, by polarizing the canopy or pilot's visor. TBH, a laser bolt in Star Wars is probably not much different than the tracer round on a real-world aircraft. It's there to act as a visual guide to show where you're shooting.
Canonically the dorsal cannon his hinged. However I think a better mechanism would be to allow the canopy to open by sliding forward, and having explosive bolts that blast the cannon clear if the pilot ejects during an emergency.

The laser blasts are more or less presented as they are in the films, although XWA goes a bit too heavy on the lighting effects (we never see laser cannon significantly lighting the cockpit of firing craft in the films, whereas in XWA laser blasts provide quite a significant light source).
Also, it's not scale, but the field of view, and how the game handles perspective and depth of field that's the question. Here's a rough test render I did with the E-wing model I ran:
The camera is set about where the pilot's viewpoint would be. You'll want to right-click > view image to see the full resolution that makes it a bit easier to estimate the FOV. This is the actual FOV I get with my display:
Having played a lot of flight sims, I'm more concerned by the visibility over the nose, because for anything other than a low-deflection shot you have to aim at a target that's well below your line of sight (the X-wing is similarly bad about this; the pilot's seat is much too low in the cockpit for good forward visibility). The cannon barrel doesn't occupy a significant enough arc of the field of view to really interfere with me, and I pretty much look PAST it. I honestly find the canopy frame to be a bigger obstruction.

Take this as you will, but after flying the E-wing in mods for X-Wing: Alliance I found the overhead gun offered very little obstruction (especially that an advanced HUD couldn’t compensate for) and the laser blasts weren’t much of a distraction.
Yeah, it’s a 20 year-old sim, but it still works as a model.

You have to be careful with stuff like that, though, because sometimes what the books describe doesn't match what we actually see on the films (ESPECIALLY in the Bantam era, where things were much less consistent). Blaster and laser fire in the films has never been shown to adversely affect human vision, nor did the firing of the X-wing or TIE fighters' cannon create any sort of significant or blinding muzzle flash. You've got the bolt, and that's pretty much it. It's like the whole thing with lightsabers being used as flashlights in the books, even though it's VERY clearly shown in the films that the emissions of a lightsaber blade don't extend much further than the surface of the blade itself (****, lightsaber blades CAST SHADOWS in the films!).
Additionally, the tip of the E-wing's cannon is also positioned in such a way that even if there WERE a muzzle flash, it would be largely obscured by the cannon itself. And considering we have polarizing lenses TODAY that can protect the eye from that really big ball of plasma we call the "Sun" and allow you to see clearly even when it's low on the horizon and right in your face, it's laughable that no one thinks they couldn't just make the E-wing's entire canopy out of that stuff.
And if the E-wing's top gun has a flash problem, I pity WWI pilots, who had machine guns firing virtually right in their faces.

Sadder news today:
George Mendonsa, the sailor captured in the legendary V-J Day In Times Square photograph, passed away today at the age of 95. Mendonsa, a sailor aboard USS The Sullivans, was on leave in New York when Japan's surrender was announced. Although the identity of the man has long been subject of debate, it's now generally accepted that Mendonsa was the man depicted kissing Greta Zimmer Friedman, then a dental hygienist. Friedman, who escaped Nazi-occupied Europe at the outset of the War, passed away in 2016.

https://www.cnn.com/2019/02/12/us/world-war-ii-aircraft-carrier-found-south-pacific-trnd/index.html
The research vessel RV Petrel, almost one year after locating the remains of USS Lexington in the Coral Sea, has located the wreck of USS Hornet on February 12. The third of the three Yorktown-class aircraft carriers, Hornet was perhaps most famous as the launch ship for Doolittle's Raid on Tokyo. She also holds the distinction as being the last US fleet carrier to be sunk by enemy action (several light and escort carriers were sunk later in the war, including St. Lo and Gambier Bay at the Battle Off Samar).
Seeing combat at the Battle of Midway with her sisters Yorktown and Enterprise, Hornet later fought in the subsequent Guadalcanal campaign, helping to support landing, and safeguarding operations to reinforce the island with elements of the Seventh Marine Regiment alongside Wasp. Hornet fought alongside Enterprise at both the Battle of the Eastern Solomons in August, 1942, and her final stand at the Battle of Santa Cruz two months later that October. She sank in over 17,000 feet of water as a result of bomb and torpedo damage, and had been lost for 77 years. Her discovery leaves Wasp — sunk by Japanese submarine I-19 in September 1942 — as the only remaining American fleet carrier wreck unaccounted for, with Yorktown having previously been located by Robert Ballard in 1998.
The rediscovery of Hornet is just the latest of many such explorations undertaken by Petrel. In addition to Lexington in March, 2018, Petrel also relocated the wrecks of USS Juneau — made famous by the deaths of the five Sullivan Brothers — and USS Helena in that year. A previous expedition by Petrel in 2017 uncovered the wreckage of USS Ward, which fired the first American shots of World War II when she depth charged a Japanese mini sub prowling outside Pearl Harbor hours before the arrival of the air attack. Additionally, a week before Hornet's discovery Petrel located the Japanese battleship Hiei in the waters off the Solomon Islands.
In order to protect Hornet's remains, and because of her status as a war grave, the exact position of her final resting place is being kept secret.

I really hate how Nucanon has mucked about with the timeline of fighter development. Since when was the TIE Avenger (which AFAIK has always been considered synonymous with the TIE Advanced from TIE Fighter, XvT, and XWA — definitively a later craft than the Squint) a predecessor to the TIE Interceptor?

That's because they designed the game with the intention of people having to find it themselves, while talking to each other and sharing the secrets as they uncover them.
Today's games offer WAY too much hand-holding. I doubt kids who grow up on today's games could ever complete a classic Sierra adventure game without a guide book (****, I grew up with Sierra, and there's still some games I could never finish).

God I miss the days of walking into CompUSA or Best Buy, and browsing aisles upon aisles of games (my CompUSA had four FULL aisles for PC games). Now you're lucky to see PART of an end cap.
Although for Consoles you have to go back to the early 90s. The SNES STILL has the best library of any console ever made.